Lewis lawson



4 (No Model.)

L. LAWSON. V

HAND SAW. 1

11101 248945. Patented Oct. 11,1881.

Wo'fizeddw? I h anior i UNITED STATES PATENT OFFICE.-

LEWIS LAWSON, OF NEW YORK, N. Y.

HAN-DSAW.

SPECIFICATION forming part of Letters Patent No. 248,045, dated October 11', 1881,

Application filed March 11, 1881.

To all whom it may concern Be it known that I, LEWIS LAWSON, a citizen of the United States, residing at the city of New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Hanging Butchers and other Saws; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters or figures-of reference marked thereon, which form a part of this specification.

This invention particularly relates to. improvements in hanging butchers and other open-back saws, so that the saw-blade may be removed and replaced by another in afewminutes without taking to a machine-shop for repair.

Having this end inview, my invention consists in first cutting a horizontal recess similar to the rigid jaws of a wrench in the lower part of the front limb, c, of the back B, Fig. 1, and also splitting the end of the limb c edgewise upward to receive the thin blade 8 of the saw and to allow the stop-pin P to pass into the recess or jaws n. This pin passes through the blade 8, and is secured to it, so as to form a part of the said saw-blade. This short pin may be a screw or simply plain, as shown in the accompanying drawings, so as to pass through and project an eighth of an inch (more or less) on each side of saw-blade, so as to be caught and firmly held in the rigid jaws n.

The back or opposite end of the saw-blade s has a similar pin, P, to hold the blade in the rigid jaws or recess it cut in the circular head V of an adjustable horizontal screw-bolt, E, which moves longitudinally through the rectangular loop or eye X, forming a part of the extreme end of the back limb, c. This adjustable screw-bolt E has a flat circular head, V, with a recess or rigid jaws, n, cutdiagonally upward in the lower edge thereof, in the fore part of the jaws of a wrench. Said head Vis also split ed gewise to receive the back end or heel of the saw-blade s, with its stop-pin P,

(No model.)

when pressed into position, before the front end of the blade is entered into the end of the front limb, c, aforesaid. The shank of this movable bolt E immediately back of the head V is of a rectangular shape,to fit into theloop or eye X, and to prevent the boltE from turning while being drawn into position by the set nut and screw It upon the threaded end of the aforesaid bolt E, to tighten and draw the saw into the position shown at A, Fig. 1, ready for use.

Fig. -2 is a side view of the adjustable bolt E, showing the fiat circular head V, square shank, and thumb-nut R on the threaded end of said bolt. Fig. 3'is an edge view of a section of the end of the back limb, 0, showing a portion of the square shank E and loop or eye X, through which the adjusting-bolt opcrates to either tighten or loosen the saw-blade s by 'the thumb screw or nut R. Fig. 4 is an edge view of the lower section of the front limb, 0, of the back B, showing the pin and front end of the saw 8 in position. 7

Having set forth the several parts of my invention, I would here state that its novelty consists (in an open-back saw) in having its extreme ends or limbs so constructed that the blade or saw may be quickly removed and replaced by another blade by simply unscrewing the thumb nut R, which can be done by any person of ordinary judgment, without having to send it to the blacksmith or machinist, by slitting the front limb, c, edgewise and cutting a longitudinal recess similar to the jaws of a wrench, to receive the transverse pin 1, passing through the end of said saw-plate and forming the end of the back limb, c, of the frame or back B into a square opening or loop to receive and operate the movable bolt. hav

ing its circular head slitted and notched in a similar manner to the front limb, c, to receive provement on saw-backs is not my invent-ion;

1. The slotted end of the front limb, c, of E, and open jaws n in the front of'the limb 0, IO the back B, with the recess or jaws n, in comall constructed,arrange(l,andoperating as and bination with the adjustable horizontal screwfor the purpose set forth. bolt E, (with regulating set-nut R,l operating In testimony whereof I affix my signature 5 in the square loop or eye X, to adjust and sein presence of two witnesses.

cure the saw blade 8, in the manner and for LEWIS LAWSON. the purpose substantially as above set forth. Witnesses:

2. The pins P P, in combination with the JAMES P. MGLEAN,

openjaws n in the head of the adjustable bolt GEO. O. BRAINERD. 

